Pull acpi_bus_register_driver into release branch
[linux-2.6] / drivers / usb / gadget / inode.c
1 /*
2  * inode.c -- user mode filesystem api for usb gadget controllers
3  *
4  * Copyright (C) 2003-2004 David Brownell
5  * Copyright (C) 2003 Agilent Technologies
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation; either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License
18  * along with this program; if not, write to the Free Software
19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21
22
23 // #define      DEBUG                   /* data to help fault diagnosis */
24 // #define      VERBOSE         /* extra debug messages (success too) */
25
26 #include <linux/init.h>
27 #include <linux/module.h>
28 #include <linux/fs.h>
29 #include <linux/pagemap.h>
30 #include <linux/uts.h>
31 #include <linux/wait.h>
32 #include <linux/compiler.h>
33 #include <asm/uaccess.h>
34 #include <linux/slab.h>
35
36 #include <linux/device.h>
37 #include <linux/moduleparam.h>
38
39 #include <linux/usb_gadgetfs.h>
40 #include <linux/usb_gadget.h>
41
42
43 /*
44  * The gadgetfs API maps each endpoint to a file descriptor so that you
45  * can use standard synchronous read/write calls for I/O.  There's some
46  * O_NONBLOCK and O_ASYNC/FASYNC style i/o support.  Example usermode
47  * drivers show how this works in practice.  You can also use AIO to
48  * eliminate I/O gaps between requests, to help when streaming data.
49  *
50  * Key parts that must be USB-specific are protocols defining how the
51  * read/write operations relate to the hardware state machines.  There
52  * are two types of files.  One type is for the device, implementing ep0.
53  * The other type is for each IN or OUT endpoint.  In both cases, the
54  * user mode driver must configure the hardware before using it.
55  *
56  * - First, dev_config() is called when /dev/gadget/$CHIP is configured
57  *   (by writing configuration and device descriptors).  Afterwards it
58  *   may serve as a source of device events, used to handle all control
59  *   requests other than basic enumeration.
60  *
61  * - Then either immediately, or after a SET_CONFIGURATION control request,
62  *   ep_config() is called when each /dev/gadget/ep* file is configured
63  *   (by writing endpoint descriptors).  Afterwards these files are used
64  *   to write() IN data or to read() OUT data.  To halt the endpoint, a
65  *   "wrong direction" request is issued (like reading an IN endpoint).
66  *
67  * Unlike "usbfs" the only ioctl()s are for things that are rare, and maybe
68  * not possible on all hardware.  For example, precise fault handling with
69  * respect to data left in endpoint fifos after aborted operations; or
70  * selective clearing of endpoint halts, to implement SET_INTERFACE.
71  */
72
73 #define DRIVER_DESC     "USB Gadget filesystem"
74 #define DRIVER_VERSION  "24 Aug 2004"
75
76 static const char driver_desc [] = DRIVER_DESC;
77 static const char shortname [] = "gadgetfs";
78
79 MODULE_DESCRIPTION (DRIVER_DESC);
80 MODULE_AUTHOR ("David Brownell");
81 MODULE_LICENSE ("GPL");
82
83
84 /*----------------------------------------------------------------------*/
85
86 #define GADGETFS_MAGIC          0xaee71ee7
87 #define DMA_ADDR_INVALID        (~(dma_addr_t)0)
88
89 /* /dev/gadget/$CHIP represents ep0 and the whole device */
90 enum ep0_state {
91         /* DISBLED is the initial state.
92          */
93         STATE_DEV_DISABLED = 0,
94
95         /* Only one open() of /dev/gadget/$CHIP; only one file tracks
96          * ep0/device i/o modes and binding to the controller.  Driver
97          * must always write descriptors to initialize the device, then
98          * the device becomes UNCONNECTED until enumeration.
99          */
100         STATE_OPENED,
101
102         /* From then on, ep0 fd is in either of two basic modes:
103          * - (UN)CONNECTED: read usb_gadgetfs_event(s) from it
104          * - SETUP: read/write will transfer control data and succeed;
105          *   or if "wrong direction", performs protocol stall
106          */
107         STATE_UNCONNECTED,
108         STATE_CONNECTED,
109         STATE_SETUP,
110
111         /* UNBOUND means the driver closed ep0, so the device won't be
112          * accessible again (DEV_DISABLED) until all fds are closed.
113          */
114         STATE_DEV_UNBOUND,
115 };
116
117 /* enough for the whole queue: most events invalidate others */
118 #define N_EVENT                 5
119
120 struct dev_data {
121         spinlock_t                      lock;
122         atomic_t                        count;
123         enum ep0_state                  state;
124         struct usb_gadgetfs_event       event [N_EVENT];
125         unsigned                        ev_next;
126         struct fasync_struct            *fasync;
127         u8                              current_config;
128
129         /* drivers reading ep0 MUST handle control requests (SETUP)
130          * reported that way; else the host will time out.
131          */
132         unsigned                        usermode_setup : 1,
133                                         setup_in : 1,
134                                         setup_can_stall : 1,
135                                         setup_out_ready : 1,
136                                         setup_out_error : 1,
137                                         setup_abort : 1;
138         unsigned                        setup_wLength;
139
140         /* the rest is basically write-once */
141         struct usb_config_descriptor    *config, *hs_config;
142         struct usb_device_descriptor    *dev;
143         struct usb_request              *req;
144         struct usb_gadget               *gadget;
145         struct list_head                epfiles;
146         void                            *buf;
147         wait_queue_head_t               wait;
148         struct super_block              *sb;
149         struct dentry                   *dentry;
150
151         /* except this scratch i/o buffer for ep0 */
152         u8                              rbuf [256];
153 };
154
155 static inline void get_dev (struct dev_data *data)
156 {
157         atomic_inc (&data->count);
158 }
159
160 static void put_dev (struct dev_data *data)
161 {
162         if (likely (!atomic_dec_and_test (&data->count)))
163                 return;
164         /* needs no more cleanup */
165         BUG_ON (waitqueue_active (&data->wait));
166         kfree (data);
167 }
168
169 static struct dev_data *dev_new (void)
170 {
171         struct dev_data         *dev;
172
173         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
174         if (!dev)
175                 return NULL;
176         dev->state = STATE_DEV_DISABLED;
177         atomic_set (&dev->count, 1);
178         spin_lock_init (&dev->lock);
179         INIT_LIST_HEAD (&dev->epfiles);
180         init_waitqueue_head (&dev->wait);
181         return dev;
182 }
183
184 /*----------------------------------------------------------------------*/
185
186 /* other /dev/gadget/$ENDPOINT files represent endpoints */
187 enum ep_state {
188         STATE_EP_DISABLED = 0,
189         STATE_EP_READY,
190         STATE_EP_DEFER_ENABLE,
191         STATE_EP_ENABLED,
192         STATE_EP_UNBOUND,
193 };
194
195 struct ep_data {
196         struct semaphore                lock;
197         enum ep_state                   state;
198         atomic_t                        count;
199         struct dev_data                 *dev;
200         /* must hold dev->lock before accessing ep or req */
201         struct usb_ep                   *ep;
202         struct usb_request              *req;
203         ssize_t                         status;
204         char                            name [16];
205         struct usb_endpoint_descriptor  desc, hs_desc;
206         struct list_head                epfiles;
207         wait_queue_head_t               wait;
208         struct dentry                   *dentry;
209         struct inode                    *inode;
210 };
211
212 static inline void get_ep (struct ep_data *data)
213 {
214         atomic_inc (&data->count);
215 }
216
217 static void put_ep (struct ep_data *data)
218 {
219         if (likely (!atomic_dec_and_test (&data->count)))
220                 return;
221         put_dev (data->dev);
222         /* needs no more cleanup */
223         BUG_ON (!list_empty (&data->epfiles));
224         BUG_ON (waitqueue_active (&data->wait));
225         BUG_ON (down_trylock (&data->lock) != 0);
226         kfree (data);
227 }
228
229 /*----------------------------------------------------------------------*/
230
231 /* most "how to use the hardware" policy choices are in userspace:
232  * mapping endpoint roles (which the driver needs) to the capabilities
233  * which the usb controller has.  most of those capabilities are exposed
234  * implicitly, starting with the driver name and then endpoint names.
235  */
236
237 static const char *CHIP;
238
239 /*----------------------------------------------------------------------*/
240
241 /* NOTE:  don't use dev_printk calls before binding to the gadget
242  * at the end of ep0 configuration, or after unbind.
243  */
244
245 /* too wordy: dev_printk(level , &(d)->gadget->dev , fmt , ## args) */
246 #define xprintk(d,level,fmt,args...) \
247         printk(level "%s: " fmt , shortname , ## args)
248
249 #ifdef DEBUG
250 #define DBG(dev,fmt,args...) \
251         xprintk(dev , KERN_DEBUG , fmt , ## args)
252 #else
253 #define DBG(dev,fmt,args...) \
254         do { } while (0)
255 #endif /* DEBUG */
256
257 #ifdef VERBOSE
258 #define VDEBUG  DBG
259 #else
260 #define VDEBUG(dev,fmt,args...) \
261         do { } while (0)
262 #endif /* DEBUG */
263
264 #define ERROR(dev,fmt,args...) \
265         xprintk(dev , KERN_ERR , fmt , ## args)
266 #define WARN(dev,fmt,args...) \
267         xprintk(dev , KERN_WARNING , fmt , ## args)
268 #define INFO(dev,fmt,args...) \
269         xprintk(dev , KERN_INFO , fmt , ## args)
270
271
272 /*----------------------------------------------------------------------*/
273
274 /* SYNCHRONOUS ENDPOINT OPERATIONS (bulk/intr/iso)
275  *
276  * After opening, configure non-control endpoints.  Then use normal
277  * stream read() and write() requests; and maybe ioctl() to get more
278  * precise FIFO status when recovering from cancellation.
279  */
280
281 static void epio_complete (struct usb_ep *ep, struct usb_request *req)
282 {
283         struct ep_data  *epdata = ep->driver_data;
284
285         if (!req->context)
286                 return;
287         if (req->status)
288                 epdata->status = req->status;
289         else
290                 epdata->status = req->actual;
291         complete ((struct completion *)req->context);
292 }
293
294 /* tasklock endpoint, returning when it's connected.
295  * still need dev->lock to use epdata->ep.
296  */
297 static int
298 get_ready_ep (unsigned f_flags, struct ep_data *epdata)
299 {
300         int     val;
301
302         if (f_flags & O_NONBLOCK) {
303                 if (down_trylock (&epdata->lock) != 0)
304                         goto nonblock;
305                 if (epdata->state != STATE_EP_ENABLED) {
306                         up (&epdata->lock);
307 nonblock:
308                         val = -EAGAIN;
309                 } else
310                         val = 0;
311                 return val;
312         }
313
314         if ((val = down_interruptible (&epdata->lock)) < 0)
315                 return val;
316 newstate:
317         switch (epdata->state) {
318         case STATE_EP_ENABLED:
319                 break;
320         case STATE_EP_DEFER_ENABLE:
321                 DBG (epdata->dev, "%s wait for host\n", epdata->name);
322                 if ((val = wait_event_interruptible (epdata->wait, 
323                                 epdata->state != STATE_EP_DEFER_ENABLE
324                                 || epdata->dev->state == STATE_DEV_UNBOUND
325                                 )) < 0)
326                         goto fail;
327                 goto newstate;
328         // case STATE_EP_DISABLED:              /* "can't happen" */
329         // case STATE_EP_READY:                 /* "can't happen" */
330         default:                                /* error! */
331                 pr_debug ("%s: ep %p not available, state %d\n",
332                                 shortname, epdata, epdata->state);
333                 // FALLTHROUGH
334         case STATE_EP_UNBOUND:                  /* clean disconnect */
335                 val = -ENODEV;
336 fail:
337                 up (&epdata->lock);
338         }
339         return val;
340 }
341
342 static ssize_t
343 ep_io (struct ep_data *epdata, void *buf, unsigned len)
344 {
345         DECLARE_COMPLETION (done);
346         int value;
347
348         spin_lock_irq (&epdata->dev->lock);
349         if (likely (epdata->ep != NULL)) {
350                 struct usb_request      *req = epdata->req;
351
352                 req->context = &done;
353                 req->complete = epio_complete;
354                 req->buf = buf;
355                 req->length = len;
356                 value = usb_ep_queue (epdata->ep, req, GFP_ATOMIC);
357         } else
358                 value = -ENODEV;
359         spin_unlock_irq (&epdata->dev->lock);
360
361         if (likely (value == 0)) {
362                 value = wait_event_interruptible (done.wait, done.done);
363                 if (value != 0) {
364                         spin_lock_irq (&epdata->dev->lock);
365                         if (likely (epdata->ep != NULL)) {
366                                 DBG (epdata->dev, "%s i/o interrupted\n",
367                                                 epdata->name);
368                                 usb_ep_dequeue (epdata->ep, epdata->req);
369                                 spin_unlock_irq (&epdata->dev->lock);
370
371                                 wait_event (done.wait, done.done);
372                                 if (epdata->status == -ECONNRESET)
373                                         epdata->status = -EINTR;
374                         } else {
375                                 spin_unlock_irq (&epdata->dev->lock);
376
377                                 DBG (epdata->dev, "endpoint gone\n");
378                                 epdata->status = -ENODEV;
379                         }
380                 }
381                 return epdata->status;
382         }
383         return value;
384 }
385
386
387 /* handle a synchronous OUT bulk/intr/iso transfer */
388 static ssize_t
389 ep_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
390 {
391         struct ep_data          *data = fd->private_data;
392         void                    *kbuf;
393         ssize_t                 value;
394
395         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
396                 return value;
397
398         /* halt any endpoint by doing a "wrong direction" i/o call */
399         if (data->desc.bEndpointAddress & USB_DIR_IN) {
400                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
401                                 == USB_ENDPOINT_XFER_ISOC)
402                         return -EINVAL;
403                 DBG (data->dev, "%s halt\n", data->name);
404                 spin_lock_irq (&data->dev->lock);
405                 if (likely (data->ep != NULL))
406                         usb_ep_set_halt (data->ep);
407                 spin_unlock_irq (&data->dev->lock);
408                 up (&data->lock);
409                 return -EBADMSG;
410         }
411
412         /* FIXME readahead for O_NONBLOCK and poll(); careful with ZLPs */
413
414         value = -ENOMEM;
415         kbuf = kmalloc (len, SLAB_KERNEL);
416         if (unlikely (!kbuf))
417                 goto free1;
418
419         value = ep_io (data, kbuf, len);
420         VDEBUG (data->dev, "%s read %zu OUT, status %d\n",
421                 data->name, len, (int) value);
422         if (value >= 0 && copy_to_user (buf, kbuf, value))
423                 value = -EFAULT;
424
425 free1:
426         up (&data->lock);
427         kfree (kbuf);
428         return value;
429 }
430
431 /* handle a synchronous IN bulk/intr/iso transfer */
432 static ssize_t
433 ep_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
434 {
435         struct ep_data          *data = fd->private_data;
436         void                    *kbuf;
437         ssize_t                 value;
438
439         if ((value = get_ready_ep (fd->f_flags, data)) < 0)
440                 return value;
441
442         /* halt any endpoint by doing a "wrong direction" i/o call */
443         if (!(data->desc.bEndpointAddress & USB_DIR_IN)) {
444                 if ((data->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
445                                 == USB_ENDPOINT_XFER_ISOC)
446                         return -EINVAL;
447                 DBG (data->dev, "%s halt\n", data->name);
448                 spin_lock_irq (&data->dev->lock);
449                 if (likely (data->ep != NULL))
450                         usb_ep_set_halt (data->ep);
451                 spin_unlock_irq (&data->dev->lock);
452                 up (&data->lock);
453                 return -EBADMSG;
454         }
455
456         /* FIXME writebehind for O_NONBLOCK and poll(), qlen = 1 */
457
458         value = -ENOMEM;
459         kbuf = kmalloc (len, SLAB_KERNEL);
460         if (!kbuf)
461                 goto free1;
462         if (copy_from_user (kbuf, buf, len)) {
463                 value = -EFAULT;
464                 goto free1;
465         }
466
467         value = ep_io (data, kbuf, len);
468         VDEBUG (data->dev, "%s write %zu IN, status %d\n",
469                 data->name, len, (int) value);
470 free1:
471         up (&data->lock);
472         kfree (kbuf);
473         return value;
474 }
475
476 static int
477 ep_release (struct inode *inode, struct file *fd)
478 {
479         struct ep_data          *data = fd->private_data;
480
481         /* clean up if this can be reopened */
482         if (data->state != STATE_EP_UNBOUND) {
483                 data->state = STATE_EP_DISABLED;
484                 data->desc.bDescriptorType = 0;
485                 data->hs_desc.bDescriptorType = 0;
486                 usb_ep_disable(data->ep);
487         }
488         put_ep (data);
489         return 0;
490 }
491
492 static int ep_ioctl (struct inode *inode, struct file *fd,
493                 unsigned code, unsigned long value)
494 {
495         struct ep_data          *data = fd->private_data;
496         int                     status;
497
498         if ((status = get_ready_ep (fd->f_flags, data)) < 0)
499                 return status;
500
501         spin_lock_irq (&data->dev->lock);
502         if (likely (data->ep != NULL)) {
503                 switch (code) {
504                 case GADGETFS_FIFO_STATUS:
505                         status = usb_ep_fifo_status (data->ep);
506                         break;
507                 case GADGETFS_FIFO_FLUSH:
508                         usb_ep_fifo_flush (data->ep);
509                         break;
510                 case GADGETFS_CLEAR_HALT:
511                         status = usb_ep_clear_halt (data->ep);
512                         break;
513                 default:
514                         status = -ENOTTY;
515                 }
516         } else
517                 status = -ENODEV;
518         spin_unlock_irq (&data->dev->lock);
519         up (&data->lock);
520         return status;
521 }
522
523 /*----------------------------------------------------------------------*/
524
525 /* ASYNCHRONOUS ENDPOINT I/O OPERATIONS (bulk/intr/iso) */
526
527 struct kiocb_priv {
528         struct usb_request      *req;
529         struct ep_data          *epdata;
530         void                    *buf;
531         char __user             *ubuf;
532         unsigned                actual;
533 };
534
535 static int ep_aio_cancel(struct kiocb *iocb, struct io_event *e)
536 {
537         struct kiocb_priv       *priv = iocb->private;
538         struct ep_data          *epdata;
539         int                     value;
540
541         local_irq_disable();
542         epdata = priv->epdata;
543         // spin_lock(&epdata->dev->lock);
544         kiocbSetCancelled(iocb);
545         if (likely(epdata && epdata->ep && priv->req))
546                 value = usb_ep_dequeue (epdata->ep, priv->req);
547         else
548                 value = -EINVAL;
549         // spin_unlock(&epdata->dev->lock);
550         local_irq_enable();
551
552         aio_put_req(iocb);
553         return value;
554 }
555
556 static ssize_t ep_aio_read_retry(struct kiocb *iocb)
557 {
558         struct kiocb_priv       *priv = iocb->private;
559         ssize_t                 status = priv->actual;
560
561         /* we "retry" to get the right mm context for this: */
562         status = copy_to_user(priv->ubuf, priv->buf, priv->actual);
563         if (unlikely(0 != status))
564                 status = -EFAULT;
565         else
566                 status = priv->actual;
567         kfree(priv->buf);
568         kfree(priv);
569         aio_put_req(iocb);
570         return status;
571 }
572
573 static void ep_aio_complete(struct usb_ep *ep, struct usb_request *req)
574 {
575         struct kiocb            *iocb = req->context;
576         struct kiocb_priv       *priv = iocb->private;
577         struct ep_data          *epdata = priv->epdata;
578
579         /* lock against disconnect (and ideally, cancel) */
580         spin_lock(&epdata->dev->lock);
581         priv->req = NULL;
582         priv->epdata = NULL;
583         if (NULL == iocb->ki_retry
584                         || unlikely(0 == req->actual)
585                         || unlikely(kiocbIsCancelled(iocb))) {
586                 kfree(req->buf);
587                 kfree(priv);
588                 iocb->private = NULL;
589                 /* aio_complete() reports bytes-transferred _and_ faults */
590                 if (unlikely(kiocbIsCancelled(iocb)))
591                         aio_put_req(iocb);
592                 else
593                         aio_complete(iocb,
594                                 req->actual ? req->actual : req->status,
595                                 req->status);
596         } else {
597                 /* retry() won't report both; so we hide some faults */
598                 if (unlikely(0 != req->status))
599                         DBG(epdata->dev, "%s fault %d len %d\n",
600                                 ep->name, req->status, req->actual);
601
602                 priv->buf = req->buf;
603                 priv->actual = req->actual;
604                 kick_iocb(iocb);
605         }
606         spin_unlock(&epdata->dev->lock);
607
608         usb_ep_free_request(ep, req);
609         put_ep(epdata);
610 }
611
612 static ssize_t
613 ep_aio_rwtail(
614         struct kiocb    *iocb,
615         char            *buf,
616         size_t          len,
617         struct ep_data  *epdata,
618         char __user     *ubuf
619 )
620 {
621         struct kiocb_priv       *priv = (void *) &iocb->private;
622         struct usb_request      *req;
623         ssize_t                 value;
624
625         priv = kmalloc(sizeof *priv, GFP_KERNEL);
626         if (!priv) {
627                 value = -ENOMEM;
628 fail:
629                 kfree(buf);
630                 return value;
631         }
632         iocb->private = priv;
633         priv->ubuf = ubuf;
634
635         value = get_ready_ep(iocb->ki_filp->f_flags, epdata);
636         if (unlikely(value < 0)) {
637                 kfree(priv);
638                 goto fail;
639         }
640
641         iocb->ki_cancel = ep_aio_cancel;
642         get_ep(epdata);
643         priv->epdata = epdata;
644         priv->actual = 0;
645
646         /* each kiocb is coupled to one usb_request, but we can't
647          * allocate or submit those if the host disconnected.
648          */
649         spin_lock_irq(&epdata->dev->lock);
650         if (likely(epdata->ep)) {
651                 req = usb_ep_alloc_request(epdata->ep, GFP_ATOMIC);
652                 if (likely(req)) {
653                         priv->req = req;
654                         req->buf = buf;
655                         req->length = len;
656                         req->complete = ep_aio_complete;
657                         req->context = iocb;
658                         value = usb_ep_queue(epdata->ep, req, GFP_ATOMIC);
659                         if (unlikely(0 != value))
660                                 usb_ep_free_request(epdata->ep, req);
661                 } else
662                         value = -EAGAIN;
663         } else
664                 value = -ENODEV;
665         spin_unlock_irq(&epdata->dev->lock);
666
667         up(&epdata->lock);
668
669         if (unlikely(value)) {
670                 kfree(priv);
671                 put_ep(epdata);
672         } else
673                 value = -EIOCBQUEUED;
674         return value;
675 }
676
677 static ssize_t
678 ep_aio_read(struct kiocb *iocb, char __user *ubuf, size_t len, loff_t o)
679 {
680         struct ep_data          *epdata = iocb->ki_filp->private_data;
681         char                    *buf;
682
683         if (unlikely(epdata->desc.bEndpointAddress & USB_DIR_IN))
684                 return -EINVAL;
685         buf = kmalloc(len, GFP_KERNEL);
686         if (unlikely(!buf))
687                 return -ENOMEM;
688         iocb->ki_retry = ep_aio_read_retry;
689         return ep_aio_rwtail(iocb, buf, len, epdata, ubuf);
690 }
691
692 static ssize_t
693 ep_aio_write(struct kiocb *iocb, const char __user *ubuf, size_t len, loff_t o)
694 {
695         struct ep_data          *epdata = iocb->ki_filp->private_data;
696         char                    *buf;
697
698         if (unlikely(!(epdata->desc.bEndpointAddress & USB_DIR_IN)))
699                 return -EINVAL;
700         buf = kmalloc(len, GFP_KERNEL);
701         if (unlikely(!buf))
702                 return -ENOMEM;
703         if (unlikely(copy_from_user(buf, ubuf, len) != 0)) {
704                 kfree(buf);
705                 return -EFAULT;
706         }
707         return ep_aio_rwtail(iocb, buf, len, epdata, NULL);
708 }
709
710 /*----------------------------------------------------------------------*/
711
712 /* used after endpoint configuration */
713 static struct file_operations ep_io_operations = {
714         .owner =        THIS_MODULE,
715         .llseek =       no_llseek,
716
717         .read =         ep_read,
718         .write =        ep_write,
719         .ioctl =        ep_ioctl,
720         .release =      ep_release,
721
722         .aio_read =     ep_aio_read,
723         .aio_write =    ep_aio_write,
724 };
725
726 /* ENDPOINT INITIALIZATION
727  *
728  *     fd = open ("/dev/gadget/$ENDPOINT", O_RDWR)
729  *     status = write (fd, descriptors, sizeof descriptors)
730  *
731  * That write establishes the endpoint configuration, configuring
732  * the controller to process bulk, interrupt, or isochronous transfers
733  * at the right maxpacket size, and so on.
734  *
735  * The descriptors are message type 1, identified by a host order u32
736  * at the beginning of what's written.  Descriptor order is: full/low
737  * speed descriptor, then optional high speed descriptor.
738  */
739 static ssize_t
740 ep_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
741 {
742         struct ep_data          *data = fd->private_data;
743         struct usb_ep           *ep;
744         u32                     tag;
745         int                     value;
746
747         if ((value = down_interruptible (&data->lock)) < 0)
748                 return value;
749
750         if (data->state != STATE_EP_READY) {
751                 value = -EL2HLT;
752                 goto fail;
753         }
754
755         value = len;
756         if (len < USB_DT_ENDPOINT_SIZE + 4)
757                 goto fail0;
758
759         /* we might need to change message format someday */
760         if (copy_from_user (&tag, buf, 4)) {
761                 goto fail1;
762         }
763         if (tag != 1) {
764                 DBG(data->dev, "config %s, bad tag %d\n", data->name, tag);
765                 goto fail0;
766         }
767         buf += 4;
768         len -= 4;
769
770         /* NOTE:  audio endpoint extensions not accepted here;
771          * just don't include the extra bytes.
772          */
773
774         /* full/low speed descriptor, then high speed */
775         if (copy_from_user (&data->desc, buf, USB_DT_ENDPOINT_SIZE)) {
776                 goto fail1;
777         }
778         if (data->desc.bLength != USB_DT_ENDPOINT_SIZE
779                         || data->desc.bDescriptorType != USB_DT_ENDPOINT)
780                 goto fail0;
781         if (len != USB_DT_ENDPOINT_SIZE) {
782                 if (len != 2 * USB_DT_ENDPOINT_SIZE)
783                         goto fail0;
784                 if (copy_from_user (&data->hs_desc, buf + USB_DT_ENDPOINT_SIZE,
785                                         USB_DT_ENDPOINT_SIZE)) {
786                         goto fail1;
787                 }
788                 if (data->hs_desc.bLength != USB_DT_ENDPOINT_SIZE
789                                 || data->hs_desc.bDescriptorType
790                                         != USB_DT_ENDPOINT) {
791                         DBG(data->dev, "config %s, bad hs length or type\n",
792                                         data->name);
793                         goto fail0;
794                 }
795         }
796         value = len;
797
798         spin_lock_irq (&data->dev->lock);
799         if (data->dev->state == STATE_DEV_UNBOUND) {
800                 value = -ENOENT;
801                 goto gone;
802         } else if ((ep = data->ep) == NULL) {
803                 value = -ENODEV;
804                 goto gone;
805         }
806         switch (data->dev->gadget->speed) {
807         case USB_SPEED_LOW:
808         case USB_SPEED_FULL:
809                 value = usb_ep_enable (ep, &data->desc);
810                 if (value == 0)
811                         data->state = STATE_EP_ENABLED;
812                 break;
813 #ifdef  CONFIG_USB_GADGET_DUALSPEED
814         case USB_SPEED_HIGH:
815                 /* fails if caller didn't provide that descriptor... */
816                 value = usb_ep_enable (ep, &data->hs_desc);
817                 if (value == 0)
818                         data->state = STATE_EP_ENABLED;
819                 break;
820 #endif
821         default:
822                 DBG (data->dev, "unconnected, %s init deferred\n",
823                                 data->name);
824                 data->state = STATE_EP_DEFER_ENABLE;
825         }
826         if (value == 0)
827                 fd->f_op = &ep_io_operations;
828 gone:
829         spin_unlock_irq (&data->dev->lock);
830         if (value < 0) {
831 fail:
832                 data->desc.bDescriptorType = 0;
833                 data->hs_desc.bDescriptorType = 0;
834         }
835         up (&data->lock);
836         return value;
837 fail0:
838         value = -EINVAL;
839         goto fail;
840 fail1:
841         value = -EFAULT;
842         goto fail;
843 }
844
845 static int
846 ep_open (struct inode *inode, struct file *fd)
847 {
848         struct ep_data          *data = inode->u.generic_ip;
849         int                     value = -EBUSY;
850
851         if (down_interruptible (&data->lock) != 0)
852                 return -EINTR;
853         spin_lock_irq (&data->dev->lock);
854         if (data->dev->state == STATE_DEV_UNBOUND)
855                 value = -ENOENT;
856         else if (data->state == STATE_EP_DISABLED) {
857                 value = 0;
858                 data->state = STATE_EP_READY;
859                 get_ep (data);
860                 fd->private_data = data;
861                 VDEBUG (data->dev, "%s ready\n", data->name);
862         } else
863                 DBG (data->dev, "%s state %d\n",
864                         data->name, data->state);
865         spin_unlock_irq (&data->dev->lock);
866         up (&data->lock);
867         return value;
868 }
869
870 /* used before endpoint configuration */
871 static struct file_operations ep_config_operations = {
872         .owner =        THIS_MODULE,
873         .llseek =       no_llseek,
874
875         .open =         ep_open,
876         .write =        ep_config,
877         .release =      ep_release,
878 };
879
880 /*----------------------------------------------------------------------*/
881
882 /* EP0 IMPLEMENTATION can be partly in userspace.
883  *
884  * Drivers that use this facility receive various events, including
885  * control requests the kernel doesn't handle.  Drivers that don't
886  * use this facility may be too simple-minded for real applications.
887  */
888
889 static inline void ep0_readable (struct dev_data *dev)
890 {
891         wake_up (&dev->wait);
892         kill_fasync (&dev->fasync, SIGIO, POLL_IN);
893 }
894
895 static void clean_req (struct usb_ep *ep, struct usb_request *req)
896 {
897         struct dev_data         *dev = ep->driver_data;
898
899         if (req->buf != dev->rbuf) {
900                 usb_ep_free_buffer (ep, req->buf, req->dma, req->length);
901                 req->buf = dev->rbuf;
902                 req->dma = DMA_ADDR_INVALID;
903         }
904         req->complete = epio_complete;
905         dev->setup_out_ready = 0;
906 }
907
908 static void ep0_complete (struct usb_ep *ep, struct usb_request *req)
909 {
910         struct dev_data         *dev = ep->driver_data;
911         int                     free = 1;
912
913         /* for control OUT, data must still get to userspace */
914         if (!dev->setup_in) {
915                 dev->setup_out_error = (req->status != 0);
916                 if (!dev->setup_out_error)
917                         free = 0;
918                 dev->setup_out_ready = 1;
919                 ep0_readable (dev);
920         } else if (dev->state == STATE_SETUP)
921                 dev->state = STATE_CONNECTED;
922
923         /* clean up as appropriate */
924         if (free && req->buf != &dev->rbuf)
925                 clean_req (ep, req);
926         req->complete = epio_complete;
927 }
928
929 static int setup_req (struct usb_ep *ep, struct usb_request *req, u16 len)
930 {
931         struct dev_data *dev = ep->driver_data;
932
933         if (dev->setup_out_ready) {
934                 DBG (dev, "ep0 request busy!\n");
935                 return -EBUSY;
936         }
937         if (len > sizeof (dev->rbuf))
938                 req->buf = usb_ep_alloc_buffer (ep, len, &req->dma, GFP_ATOMIC);
939         if (req->buf == 0) {
940                 req->buf = dev->rbuf;
941                 return -ENOMEM;
942         }
943         req->complete = ep0_complete;
944         req->length = len;
945         req->zero = 0;
946         return 0;
947 }
948
949 static ssize_t
950 ep0_read (struct file *fd, char __user *buf, size_t len, loff_t *ptr)
951 {
952         struct dev_data                 *dev = fd->private_data;
953         ssize_t                         retval;
954         enum ep0_state                  state;
955
956         spin_lock_irq (&dev->lock);
957
958         /* report fd mode change before acting on it */
959         if (dev->setup_abort) {
960                 dev->setup_abort = 0;
961                 retval = -EIDRM;
962                 goto done;
963         }
964
965         /* control DATA stage */
966         if ((state = dev->state) == STATE_SETUP) {
967
968                 if (dev->setup_in) {            /* stall IN */
969                         VDEBUG(dev, "ep0in stall\n");
970                         (void) usb_ep_set_halt (dev->gadget->ep0);
971                         retval = -EL2HLT;
972                         dev->state = STATE_CONNECTED;
973
974                 } else if (len == 0) {          /* ack SET_CONFIGURATION etc */
975                         struct usb_ep           *ep = dev->gadget->ep0;
976                         struct usb_request      *req = dev->req;
977
978                         if ((retval = setup_req (ep, req, 0)) == 0)
979                                 retval = usb_ep_queue (ep, req, GFP_ATOMIC);
980                         dev->state = STATE_CONNECTED;
981
982                         /* assume that was SET_CONFIGURATION */
983                         if (dev->current_config) {
984                                 unsigned power;
985 #ifdef  CONFIG_USB_GADGET_DUALSPEED
986                                 if (dev->gadget->speed == USB_SPEED_HIGH)
987                                         power = dev->hs_config->bMaxPower;
988                                 else
989 #endif
990                                         power = dev->config->bMaxPower;
991                                 usb_gadget_vbus_draw(dev->gadget, 2 * power);
992                         }
993
994                 } else {                        /* collect OUT data */
995                         if ((fd->f_flags & O_NONBLOCK) != 0
996                                         && !dev->setup_out_ready) {
997                                 retval = -EAGAIN;
998                                 goto done;
999                         }
1000                         spin_unlock_irq (&dev->lock);
1001                         retval = wait_event_interruptible (dev->wait,
1002                                         dev->setup_out_ready != 0);
1003
1004                         /* FIXME state could change from under us */
1005                         spin_lock_irq (&dev->lock);
1006                         if (retval)
1007                                 goto done;
1008                         if (dev->setup_out_error)
1009                                 retval = -EIO;
1010                         else {
1011                                 len = min (len, (size_t)dev->req->actual);
1012 // FIXME don't call this with the spinlock held ...
1013                                 if (copy_to_user (buf, &dev->req->buf, len))
1014                                         retval = -EFAULT;
1015                                 clean_req (dev->gadget->ep0, dev->req);
1016                                 /* NOTE userspace can't yet choose to stall */
1017                         }
1018                 }
1019                 goto done;
1020         }
1021
1022         /* else normal: return event data */
1023         if (len < sizeof dev->event [0]) {
1024                 retval = -EINVAL;
1025                 goto done;
1026         }
1027         len -= len % sizeof (struct usb_gadgetfs_event);
1028         dev->usermode_setup = 1;
1029
1030 scan:
1031         /* return queued events right away */
1032         if (dev->ev_next != 0) {
1033                 unsigned                i, n;
1034                 int                     tmp = dev->ev_next;
1035
1036                 len = min (len, tmp * sizeof (struct usb_gadgetfs_event));
1037                 n = len / sizeof (struct usb_gadgetfs_event);
1038
1039                 /* ep0 can't deliver events when STATE_SETUP */
1040                 for (i = 0; i < n; i++) {
1041                         if (dev->event [i].type == GADGETFS_SETUP) {
1042                                 len = n = i + 1;
1043                                 len *= sizeof (struct usb_gadgetfs_event);
1044                                 n = 0;
1045                                 break;
1046                         }
1047                 }
1048                 spin_unlock_irq (&dev->lock);
1049                 if (copy_to_user (buf, &dev->event, len))
1050                         retval = -EFAULT;
1051                 else
1052                         retval = len;
1053                 if (len > 0) {
1054                         len /= sizeof (struct usb_gadgetfs_event);
1055
1056                         /* NOTE this doesn't guard against broken drivers;
1057                          * concurrent ep0 readers may lose events.
1058                          */
1059                         spin_lock_irq (&dev->lock);
1060                         dev->ev_next -= len;
1061                         if (dev->ev_next != 0)
1062                                 memmove (&dev->event, &dev->event [len],
1063                                         sizeof (struct usb_gadgetfs_event)
1064                                                 * (tmp - len));
1065                         if (n == 0)
1066                                 dev->state = STATE_SETUP;
1067                         spin_unlock_irq (&dev->lock);
1068                 }
1069                 return retval;
1070         }
1071         if (fd->f_flags & O_NONBLOCK) {
1072                 retval = -EAGAIN;
1073                 goto done;
1074         }
1075
1076         switch (state) {
1077         default:
1078                 DBG (dev, "fail %s, state %d\n", __FUNCTION__, state);
1079                 retval = -ESRCH;
1080                 break;
1081         case STATE_UNCONNECTED:
1082         case STATE_CONNECTED:
1083                 spin_unlock_irq (&dev->lock);
1084                 DBG (dev, "%s wait\n", __FUNCTION__);
1085
1086                 /* wait for events */
1087                 retval = wait_event_interruptible (dev->wait,
1088                                 dev->ev_next != 0);
1089                 if (retval < 0)
1090                         return retval;
1091                 spin_lock_irq (&dev->lock);
1092                 goto scan;
1093         }
1094
1095 done:
1096         spin_unlock_irq (&dev->lock);
1097         return retval;
1098 }
1099
1100 static struct usb_gadgetfs_event *
1101 next_event (struct dev_data *dev, enum usb_gadgetfs_event_type type)
1102 {
1103         struct usb_gadgetfs_event       *event;
1104         unsigned                        i;
1105
1106         switch (type) {
1107         /* these events purge the queue */
1108         case GADGETFS_DISCONNECT:
1109                 if (dev->state == STATE_SETUP)
1110                         dev->setup_abort = 1;
1111                 // FALL THROUGH
1112         case GADGETFS_CONNECT:
1113                 dev->ev_next = 0;
1114                 break;
1115         case GADGETFS_SETUP:            /* previous request timed out */
1116         case GADGETFS_SUSPEND:          /* same effect */
1117                 /* these events can't be repeated */
1118                 for (i = 0; i != dev->ev_next; i++) {
1119                         if (dev->event [i].type != type)
1120                                 continue;
1121                         DBG (dev, "discard old event %d\n", type);
1122                         dev->ev_next--;
1123                         if (i == dev->ev_next)
1124                                 break;
1125                         /* indices start at zero, for simplicity */
1126                         memmove (&dev->event [i], &dev->event [i + 1],
1127                                 sizeof (struct usb_gadgetfs_event)
1128                                         * (dev->ev_next - i));
1129                 }
1130                 break;
1131         default:
1132                 BUG ();
1133         }
1134         event = &dev->event [dev->ev_next++];
1135         BUG_ON (dev->ev_next > N_EVENT);
1136         VDEBUG (dev, "ev %d, next %d\n", type, dev->ev_next);
1137         memset (event, 0, sizeof *event);
1138         event->type = type;
1139         return event;
1140 }
1141
1142 static ssize_t
1143 ep0_write (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1144 {
1145         struct dev_data         *dev = fd->private_data;
1146         ssize_t                 retval = -ESRCH;
1147
1148         spin_lock_irq (&dev->lock);
1149
1150         /* report fd mode change before acting on it */
1151         if (dev->setup_abort) {
1152                 dev->setup_abort = 0;
1153                 retval = -EIDRM;
1154
1155         /* data and/or status stage for control request */
1156         } else if (dev->state == STATE_SETUP) {
1157
1158                 /* IN DATA+STATUS caller makes len <= wLength */
1159                 if (dev->setup_in) {
1160                         retval = setup_req (dev->gadget->ep0, dev->req, len);
1161                         if (retval == 0) {
1162                                 spin_unlock_irq (&dev->lock);
1163                                 if (copy_from_user (dev->req->buf, buf, len))
1164                                         retval = -EFAULT;
1165                                 else {
1166                                         if (len < dev->setup_wLength)
1167                                                 dev->req->zero = 1;
1168                                         retval = usb_ep_queue (
1169                                                 dev->gadget->ep0, dev->req,
1170                                                 GFP_KERNEL);
1171                                 }
1172                                 if (retval < 0) {
1173                                         spin_lock_irq (&dev->lock);
1174                                         clean_req (dev->gadget->ep0, dev->req);
1175                                         spin_unlock_irq (&dev->lock);
1176                                 } else
1177                                         retval = len;
1178
1179                                 return retval;
1180                         }
1181
1182                 /* can stall some OUT transfers */
1183                 } else if (dev->setup_can_stall) {
1184                         VDEBUG(dev, "ep0out stall\n");
1185                         (void) usb_ep_set_halt (dev->gadget->ep0);
1186                         retval = -EL2HLT;
1187                         dev->state = STATE_CONNECTED;
1188                 } else {
1189                         DBG(dev, "bogus ep0out stall!\n");
1190                 }
1191         } else
1192                 DBG (dev, "fail %s, state %d\n", __FUNCTION__, dev->state);
1193
1194         spin_unlock_irq (&dev->lock);
1195         return retval;
1196 }
1197
1198 static int
1199 ep0_fasync (int f, struct file *fd, int on)
1200 {
1201         struct dev_data         *dev = fd->private_data;
1202         // caller must F_SETOWN before signal delivery happens
1203         VDEBUG (dev, "%s %s\n", __FUNCTION__, on ? "on" : "off");
1204         return fasync_helper (f, fd, on, &dev->fasync);
1205 }
1206
1207 static struct usb_gadget_driver gadgetfs_driver;
1208
1209 static int
1210 dev_release (struct inode *inode, struct file *fd)
1211 {
1212         struct dev_data         *dev = fd->private_data;
1213
1214         /* closing ep0 === shutdown all */
1215
1216         usb_gadget_unregister_driver (&gadgetfs_driver);
1217
1218         /* at this point "good" hardware has disconnected the
1219          * device from USB; the host won't see it any more.
1220          * alternatively, all host requests will time out.
1221          */
1222
1223         fasync_helper (-1, fd, 0, &dev->fasync);
1224         kfree (dev->buf);
1225         dev->buf = NULL;
1226         put_dev (dev);
1227
1228         /* other endpoints were all decoupled from this device */
1229         dev->state = STATE_DEV_DISABLED;
1230         return 0;
1231 }
1232
1233 static int dev_ioctl (struct inode *inode, struct file *fd,
1234                 unsigned code, unsigned long value)
1235 {
1236         struct dev_data         *dev = fd->private_data;
1237         struct usb_gadget       *gadget = dev->gadget;
1238
1239         if (gadget->ops->ioctl)
1240                 return gadget->ops->ioctl (gadget, code, value);
1241         return -ENOTTY;
1242 }
1243
1244 /* used after device configuration */
1245 static struct file_operations ep0_io_operations = {
1246         .owner =        THIS_MODULE,
1247         .llseek =       no_llseek,
1248
1249         .read =         ep0_read,
1250         .write =        ep0_write,
1251         .fasync =       ep0_fasync,
1252         // .poll =      ep0_poll,
1253         .ioctl =        dev_ioctl,
1254         .release =      dev_release,
1255 };
1256
1257 /*----------------------------------------------------------------------*/
1258
1259 /* The in-kernel gadget driver handles most ep0 issues, in particular
1260  * enumerating the single configuration (as provided from user space).
1261  *
1262  * Unrecognized ep0 requests may be handled in user space.
1263  */
1264
1265 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1266 static void make_qualifier (struct dev_data *dev)
1267 {
1268         struct usb_qualifier_descriptor         qual;
1269         struct usb_device_descriptor            *desc;
1270
1271         qual.bLength = sizeof qual;
1272         qual.bDescriptorType = USB_DT_DEVICE_QUALIFIER;
1273         qual.bcdUSB = __constant_cpu_to_le16 (0x0200);
1274
1275         desc = dev->dev;
1276         qual.bDeviceClass = desc->bDeviceClass;
1277         qual.bDeviceSubClass = desc->bDeviceSubClass;
1278         qual.bDeviceProtocol = desc->bDeviceProtocol;
1279
1280         /* assumes ep0 uses the same value for both speeds ... */
1281         qual.bMaxPacketSize0 = desc->bMaxPacketSize0;
1282
1283         qual.bNumConfigurations = 1;
1284         qual.bRESERVED = 0;
1285
1286         memcpy (dev->rbuf, &qual, sizeof qual);
1287 }
1288 #endif
1289
1290 static int
1291 config_buf (struct dev_data *dev, u8 type, unsigned index)
1292 {
1293         int             len;
1294 #ifdef CONFIG_USB_GADGET_DUALSPEED
1295         int             hs;
1296 #endif
1297
1298         /* only one configuration */
1299         if (index > 0)
1300                 return -EINVAL;
1301
1302 #ifdef CONFIG_USB_GADGET_DUALSPEED
1303         hs = (dev->gadget->speed == USB_SPEED_HIGH);
1304         if (type == USB_DT_OTHER_SPEED_CONFIG)
1305                 hs = !hs;
1306         if (hs) {
1307                 dev->req->buf = dev->hs_config;
1308                 len = le16_to_cpup (&dev->hs_config->wTotalLength);
1309         } else
1310 #endif
1311         {
1312                 dev->req->buf = dev->config;
1313                 len = le16_to_cpup (&dev->config->wTotalLength);
1314         }
1315         ((u8 *)dev->req->buf) [1] = type;
1316         return len;
1317 }
1318
1319 static int
1320 gadgetfs_setup (struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
1321 {
1322         struct dev_data                 *dev = get_gadget_data (gadget);
1323         struct usb_request              *req = dev->req;
1324         int                             value = -EOPNOTSUPP;
1325         struct usb_gadgetfs_event       *event;
1326         u16                             w_value = le16_to_cpu(ctrl->wValue);
1327         u16                             w_length = le16_to_cpu(ctrl->wLength);
1328
1329         spin_lock (&dev->lock);
1330         dev->setup_abort = 0;
1331         if (dev->state == STATE_UNCONNECTED) {
1332                 struct usb_ep   *ep;
1333                 struct ep_data  *data;
1334
1335                 dev->state = STATE_CONNECTED;
1336                 dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1337
1338 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1339                 if (gadget->speed == USB_SPEED_HIGH && dev->hs_config == 0) {
1340                         ERROR (dev, "no high speed config??\n");
1341                         return -EINVAL;
1342                 }
1343 #endif  /* CONFIG_USB_GADGET_DUALSPEED */
1344
1345                 INFO (dev, "connected\n");
1346                 event = next_event (dev, GADGETFS_CONNECT);
1347                 event->u.speed = gadget->speed;
1348                 ep0_readable (dev);
1349
1350                 list_for_each_entry (ep, &gadget->ep_list, ep_list) {
1351                         data = ep->driver_data;
1352                         /* ... down_trylock (&data->lock) ... */
1353                         if (data->state != STATE_EP_DEFER_ENABLE)
1354                                 continue;
1355 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1356                         if (gadget->speed == USB_SPEED_HIGH)
1357                                 value = usb_ep_enable (ep, &data->hs_desc);
1358                         else
1359 #endif  /* CONFIG_USB_GADGET_DUALSPEED */
1360                                 value = usb_ep_enable (ep, &data->desc);
1361                         if (value) {
1362                                 ERROR (dev, "deferred %s enable --> %d\n",
1363                                         data->name, value);
1364                                 continue;
1365                         }
1366                         data->state = STATE_EP_ENABLED;
1367                         wake_up (&data->wait);
1368                         DBG (dev, "woke up %s waiters\n", data->name);
1369                 }
1370
1371         /* host may have given up waiting for response.  we can miss control
1372          * requests handled lower down (device/endpoint status and features);
1373          * then ep0_{read,write} will report the wrong status. controller
1374          * driver will have aborted pending i/o.
1375          */
1376         } else if (dev->state == STATE_SETUP)
1377                 dev->setup_abort = 1;
1378
1379         req->buf = dev->rbuf;
1380         req->dma = DMA_ADDR_INVALID;
1381         req->context = NULL;
1382         value = -EOPNOTSUPP;
1383         switch (ctrl->bRequest) {
1384
1385         case USB_REQ_GET_DESCRIPTOR:
1386                 if (ctrl->bRequestType != USB_DIR_IN)
1387                         goto unrecognized;
1388                 switch (w_value >> 8) {
1389
1390                 case USB_DT_DEVICE:
1391                         value = min (w_length, (u16) sizeof *dev->dev);
1392                         req->buf = dev->dev;
1393                         break;
1394 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1395                 case USB_DT_DEVICE_QUALIFIER:
1396                         if (!dev->hs_config)
1397                                 break;
1398                         value = min (w_length, (u16)
1399                                 sizeof (struct usb_qualifier_descriptor));
1400                         make_qualifier (dev);
1401                         break;
1402                 case USB_DT_OTHER_SPEED_CONFIG:
1403                         // FALLTHROUGH
1404 #endif
1405                 case USB_DT_CONFIG:
1406                         value = config_buf (dev,
1407                                         w_value >> 8,
1408                                         w_value & 0xff);
1409                         if (value >= 0)
1410                                 value = min (w_length, (u16) value);
1411                         break;
1412                 case USB_DT_STRING:
1413                         goto unrecognized;
1414
1415                 default:                // all others are errors
1416                         break;
1417                 }
1418                 break;
1419
1420         /* currently one config, two speeds */
1421         case USB_REQ_SET_CONFIGURATION:
1422                 if (ctrl->bRequestType != 0)
1423                         break;
1424                 if (0 == (u8) w_value) {
1425                         value = 0;
1426                         dev->current_config = 0;
1427                         usb_gadget_vbus_draw(gadget, 8 /* mA */ );
1428                         // user mode expected to disable endpoints
1429                 } else {
1430                         u8      config, power;
1431 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1432                         if (gadget->speed == USB_SPEED_HIGH) {
1433                                 config = dev->hs_config->bConfigurationValue;
1434                                 power = dev->hs_config->bMaxPower;
1435                         } else
1436 #endif
1437                         {
1438                                 config = dev->config->bConfigurationValue;
1439                                 power = dev->config->bMaxPower;
1440                         }
1441
1442                         if (config == (u8) w_value) {
1443                                 value = 0;
1444                                 dev->current_config = config;
1445                                 usb_gadget_vbus_draw(gadget, 2 * power);
1446                         }
1447                 }
1448
1449                 /* report SET_CONFIGURATION like any other control request,
1450                  * except that usermode may not stall this.  the next
1451                  * request mustn't be allowed start until this finishes:
1452                  * endpoints and threads set up, etc.
1453                  *
1454                  * NOTE:  older PXA hardware (before PXA 255: without UDCCFR)
1455                  * has bad/racey automagic that prevents synchronizing here.
1456                  * even kernel mode drivers often miss them.
1457                  */
1458                 if (value == 0) {
1459                         INFO (dev, "configuration #%d\n", dev->current_config);
1460                         if (dev->usermode_setup) {
1461                                 dev->setup_can_stall = 0;
1462                                 goto delegate;
1463                         }
1464                 }
1465                 break;
1466
1467 #ifndef CONFIG_USB_GADGETFS_PXA2XX
1468         /* PXA automagically handles this request too */
1469         case USB_REQ_GET_CONFIGURATION:
1470                 if (ctrl->bRequestType != 0x80)
1471                         break;
1472                 *(u8 *)req->buf = dev->current_config;
1473                 value = min (w_length, (u16) 1);
1474                 break;
1475 #endif
1476
1477         default:
1478 unrecognized:
1479                 VDEBUG (dev, "%s req%02x.%02x v%04x i%04x l%d\n",
1480                         dev->usermode_setup ? "delegate" : "fail",
1481                         ctrl->bRequestType, ctrl->bRequest,
1482                         w_value, le16_to_cpu(ctrl->wIndex), w_length);
1483
1484                 /* if there's an ep0 reader, don't stall */
1485                 if (dev->usermode_setup) {
1486                         dev->setup_can_stall = 1;
1487 delegate:
1488                         dev->setup_in = (ctrl->bRequestType & USB_DIR_IN)
1489                                                 ? 1 : 0;
1490                         dev->setup_wLength = w_length;
1491                         dev->setup_out_ready = 0;
1492                         dev->setup_out_error = 0;
1493                         value = 0;
1494
1495                         /* read DATA stage for OUT right away */
1496                         if (unlikely (!dev->setup_in && w_length)) {
1497                                 value = setup_req (gadget->ep0, dev->req,
1498                                                         w_length);
1499                                 if (value < 0)
1500                                         break;
1501                                 value = usb_ep_queue (gadget->ep0, dev->req,
1502                                                         GFP_ATOMIC);
1503                                 if (value < 0) {
1504                                         clean_req (gadget->ep0, dev->req);
1505                                         break;
1506                                 }
1507
1508                                 /* we can't currently stall these */
1509                                 dev->setup_can_stall = 0;
1510                         }
1511
1512                         /* state changes when reader collects event */
1513                         event = next_event (dev, GADGETFS_SETUP);
1514                         event->u.setup = *ctrl;
1515                         ep0_readable (dev);
1516                         spin_unlock (&dev->lock);
1517                         return 0;
1518                 }
1519         }
1520
1521         /* proceed with data transfer and status phases? */
1522         if (value >= 0 && dev->state != STATE_SETUP) {
1523                 req->length = value;
1524                 req->zero = value < w_length;
1525                 value = usb_ep_queue (gadget->ep0, req, GFP_ATOMIC);
1526                 if (value < 0) {
1527                         DBG (dev, "ep_queue --> %d\n", value);
1528                         req->status = 0;
1529                 }
1530         }
1531
1532         /* device stalls when value < 0 */
1533         spin_unlock (&dev->lock);
1534         return value;
1535 }
1536
1537 static void destroy_ep_files (struct dev_data *dev)
1538 {
1539         struct list_head        *entry, *tmp;
1540
1541         DBG (dev, "%s %d\n", __FUNCTION__, dev->state);
1542
1543         /* dev->state must prevent interference */
1544 restart:
1545         spin_lock_irq (&dev->lock);
1546         list_for_each_safe (entry, tmp, &dev->epfiles) {
1547                 struct ep_data  *ep;
1548                 struct inode    *parent;
1549                 struct dentry   *dentry;
1550
1551                 /* break link to FS */
1552                 ep = list_entry (entry, struct ep_data, epfiles);
1553                 list_del_init (&ep->epfiles);
1554                 dentry = ep->dentry;
1555                 ep->dentry = NULL;
1556                 parent = dentry->d_parent->d_inode;
1557
1558                 /* break link to controller */
1559                 if (ep->state == STATE_EP_ENABLED)
1560                         (void) usb_ep_disable (ep->ep);
1561                 ep->state = STATE_EP_UNBOUND;
1562                 usb_ep_free_request (ep->ep, ep->req);
1563                 ep->ep = NULL;
1564                 wake_up (&ep->wait);
1565                 put_ep (ep);
1566
1567                 spin_unlock_irq (&dev->lock);
1568
1569                 /* break link to dcache */
1570                 mutex_lock (&parent->i_mutex);
1571                 d_delete (dentry);
1572                 dput (dentry);
1573                 mutex_unlock (&parent->i_mutex);
1574
1575                 /* fds may still be open */
1576                 goto restart;
1577         }
1578         spin_unlock_irq (&dev->lock);
1579 }
1580
1581
1582 static struct inode *
1583 gadgetfs_create_file (struct super_block *sb, char const *name,
1584                 void *data, const struct file_operations *fops,
1585                 struct dentry **dentry_p);
1586
1587 static int activate_ep_files (struct dev_data *dev)
1588 {
1589         struct usb_ep   *ep;
1590
1591         gadget_for_each_ep (ep, dev->gadget) {
1592                 struct ep_data  *data;
1593
1594                 data = kzalloc(sizeof(*data), GFP_KERNEL);
1595                 if (!data)
1596                         goto enomem;
1597                 data->state = STATE_EP_DISABLED;
1598                 init_MUTEX (&data->lock);
1599                 init_waitqueue_head (&data->wait);
1600
1601                 strncpy (data->name, ep->name, sizeof (data->name) - 1);
1602                 atomic_set (&data->count, 1);
1603                 data->dev = dev;
1604                 get_dev (dev);
1605
1606                 data->ep = ep;
1607                 ep->driver_data = data;
1608
1609                 data->req = usb_ep_alloc_request (ep, GFP_KERNEL);
1610                 if (!data->req)
1611                         goto enomem;
1612
1613                 data->inode = gadgetfs_create_file (dev->sb, data->name,
1614                                 data, &ep_config_operations,
1615                                 &data->dentry);
1616                 if (!data->inode) {
1617                         usb_ep_free_request(ep, data->req);
1618                         kfree (data);
1619                         goto enomem;
1620                 }
1621                 list_add_tail (&data->epfiles, &dev->epfiles);
1622         }
1623         return 0;
1624
1625 enomem:
1626         DBG (dev, "%s enomem\n", __FUNCTION__);
1627         destroy_ep_files (dev);
1628         return -ENOMEM;
1629 }
1630
1631 static void
1632 gadgetfs_unbind (struct usb_gadget *gadget)
1633 {
1634         struct dev_data         *dev = get_gadget_data (gadget);
1635
1636         DBG (dev, "%s\n", __FUNCTION__);
1637
1638         spin_lock_irq (&dev->lock);
1639         dev->state = STATE_DEV_UNBOUND;
1640         spin_unlock_irq (&dev->lock);
1641
1642         destroy_ep_files (dev);
1643         gadget->ep0->driver_data = NULL;
1644         set_gadget_data (gadget, NULL);
1645
1646         /* we've already been disconnected ... no i/o is active */
1647         if (dev->req)
1648                 usb_ep_free_request (gadget->ep0, dev->req);
1649         DBG (dev, "%s done\n", __FUNCTION__);
1650         put_dev (dev);
1651 }
1652
1653 static struct dev_data          *the_device;
1654
1655 static int
1656 gadgetfs_bind (struct usb_gadget *gadget)
1657 {
1658         struct dev_data         *dev = the_device;
1659
1660         if (!dev)
1661                 return -ESRCH;
1662         if (0 != strcmp (CHIP, gadget->name)) {
1663                 printk (KERN_ERR "%s expected %s controller not %s\n",
1664                         shortname, CHIP, gadget->name);
1665                 return -ENODEV;
1666         }
1667
1668         set_gadget_data (gadget, dev);
1669         dev->gadget = gadget;
1670         gadget->ep0->driver_data = dev;
1671         dev->dev->bMaxPacketSize0 = gadget->ep0->maxpacket;
1672
1673         /* preallocate control response and buffer */
1674         dev->req = usb_ep_alloc_request (gadget->ep0, GFP_KERNEL);
1675         if (!dev->req)
1676                 goto enomem;
1677         dev->req->context = NULL;
1678         dev->req->complete = epio_complete;
1679
1680         if (activate_ep_files (dev) < 0)
1681                 goto enomem;
1682
1683         INFO (dev, "bound to %s driver\n", gadget->name);
1684         dev->state = STATE_UNCONNECTED;
1685         get_dev (dev);
1686         return 0;
1687
1688 enomem:
1689         gadgetfs_unbind (gadget);
1690         return -ENOMEM;
1691 }
1692
1693 static void
1694 gadgetfs_disconnect (struct usb_gadget *gadget)
1695 {
1696         struct dev_data         *dev = get_gadget_data (gadget);
1697
1698         if (dev->state == STATE_UNCONNECTED) {
1699                 DBG (dev, "already unconnected\n");
1700                 return;
1701         }
1702         dev->state = STATE_UNCONNECTED;
1703
1704         INFO (dev, "disconnected\n");
1705         spin_lock (&dev->lock);
1706         next_event (dev, GADGETFS_DISCONNECT);
1707         ep0_readable (dev);
1708         spin_unlock (&dev->lock);
1709 }
1710
1711 static void
1712 gadgetfs_suspend (struct usb_gadget *gadget)
1713 {
1714         struct dev_data         *dev = get_gadget_data (gadget);
1715
1716         INFO (dev, "suspended from state %d\n", dev->state);
1717         spin_lock (&dev->lock);
1718         switch (dev->state) {
1719         case STATE_SETUP:               // VERY odd... host died??
1720         case STATE_CONNECTED:
1721         case STATE_UNCONNECTED:
1722                 next_event (dev, GADGETFS_SUSPEND);
1723                 ep0_readable (dev);
1724                 /* FALLTHROUGH */
1725         default:
1726                 break;
1727         }
1728         spin_unlock (&dev->lock);
1729 }
1730
1731 static struct usb_gadget_driver gadgetfs_driver = {
1732 #ifdef  CONFIG_USB_GADGET_DUALSPEED
1733         .speed          = USB_SPEED_HIGH,
1734 #else
1735         .speed          = USB_SPEED_FULL,
1736 #endif
1737         .function       = (char *) driver_desc,
1738         .bind           = gadgetfs_bind,
1739         .unbind         = gadgetfs_unbind,
1740         .setup          = gadgetfs_setup,
1741         .disconnect     = gadgetfs_disconnect,
1742         .suspend        = gadgetfs_suspend,
1743
1744         .driver         = {
1745                 .name           = (char *) shortname,
1746         },
1747 };
1748
1749 /*----------------------------------------------------------------------*/
1750
1751 static void gadgetfs_nop(struct usb_gadget *arg) { }
1752
1753 static int gadgetfs_probe (struct usb_gadget *gadget)
1754 {
1755         CHIP = gadget->name;
1756         return -EISNAM;
1757 }
1758
1759 static struct usb_gadget_driver probe_driver = {
1760         .speed          = USB_SPEED_HIGH,
1761         .bind           = gadgetfs_probe,
1762         .unbind         = gadgetfs_nop,
1763         .setup          = (void *)gadgetfs_nop,
1764         .disconnect     = gadgetfs_nop,
1765         .driver         = {
1766                 .name           = "nop",
1767         },
1768 };
1769
1770
1771 /* DEVICE INITIALIZATION
1772  *
1773  *     fd = open ("/dev/gadget/$CHIP", O_RDWR)
1774  *     status = write (fd, descriptors, sizeof descriptors)
1775  *
1776  * That write establishes the device configuration, so the kernel can
1777  * bind to the controller ... guaranteeing it can handle enumeration
1778  * at all necessary speeds.  Descriptor order is:
1779  *
1780  * . message tag (u32, host order) ... for now, must be zero; it
1781  *      would change to support features like multi-config devices
1782  * . full/low speed config ... all wTotalLength bytes (with interface,
1783  *      class, altsetting, endpoint, and other descriptors)
1784  * . high speed config ... all descriptors, for high speed operation;
1785  *      this one's optional except for high-speed hardware
1786  * . device descriptor
1787  *
1788  * Endpoints are not yet enabled. Drivers may want to immediately
1789  * initialize them, using the /dev/gadget/ep* files that are available
1790  * as soon as the kernel sees the configuration, or they can wait
1791  * until device configuration and interface altsetting changes create
1792  * the need to configure (or unconfigure) them.
1793  *
1794  * After initialization, the device stays active for as long as that
1795  * $CHIP file is open.  Events may then be read from that descriptor,
1796  * such configuration notifications.  More complex drivers will handle
1797  * some control requests in user space.
1798  */
1799
1800 static int is_valid_config (struct usb_config_descriptor *config)
1801 {
1802         return config->bDescriptorType == USB_DT_CONFIG
1803                 && config->bLength == USB_DT_CONFIG_SIZE
1804                 && config->bConfigurationValue != 0
1805                 && (config->bmAttributes & USB_CONFIG_ATT_ONE) != 0
1806                 && (config->bmAttributes & USB_CONFIG_ATT_WAKEUP) == 0;
1807         /* FIXME if gadget->is_otg, _must_ include an otg descriptor */
1808         /* FIXME check lengths: walk to end */
1809 }
1810
1811 static ssize_t
1812 dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
1813 {
1814         struct dev_data         *dev = fd->private_data;
1815         ssize_t                 value = len, length = len;
1816         unsigned                total;
1817         u32                     tag;
1818         char                    *kbuf;
1819
1820         if (dev->state != STATE_OPENED)
1821                 return -EEXIST;
1822
1823         if (len < (USB_DT_CONFIG_SIZE + USB_DT_DEVICE_SIZE + 4))
1824                 return -EINVAL;
1825
1826         /* we might need to change message format someday */
1827         if (copy_from_user (&tag, buf, 4))
1828                 return -EFAULT;
1829         if (tag != 0)
1830                 return -EINVAL;
1831         buf += 4;
1832         length -= 4;
1833
1834         kbuf = kmalloc (length, SLAB_KERNEL);
1835         if (!kbuf)
1836                 return -ENOMEM;
1837         if (copy_from_user (kbuf, buf, length)) {
1838                 kfree (kbuf);
1839                 return -EFAULT;
1840         }
1841
1842         spin_lock_irq (&dev->lock);
1843         value = -EINVAL;
1844         if (dev->buf)
1845                 goto fail;
1846         dev->buf = kbuf;
1847
1848         /* full or low speed config */
1849         dev->config = (void *) kbuf;
1850         total = le16_to_cpup (&dev->config->wTotalLength);
1851         if (!is_valid_config (dev->config) || total >= length)
1852                 goto fail;
1853         kbuf += total;
1854         length -= total;
1855
1856         /* optional high speed config */
1857         if (kbuf [1] == USB_DT_CONFIG) {
1858                 dev->hs_config = (void *) kbuf;
1859                 total = le16_to_cpup (&dev->hs_config->wTotalLength);
1860                 if (!is_valid_config (dev->hs_config) || total >= length)
1861                         goto fail;
1862                 kbuf += total;
1863                 length -= total;
1864         }
1865
1866         /* could support multiple configs, using another encoding! */
1867
1868         /* device descriptor (tweaked for paranoia) */
1869         if (length != USB_DT_DEVICE_SIZE)
1870                 goto fail;
1871         dev->dev = (void *)kbuf;
1872         if (dev->dev->bLength != USB_DT_DEVICE_SIZE
1873                         || dev->dev->bDescriptorType != USB_DT_DEVICE
1874                         || dev->dev->bNumConfigurations != 1)
1875                 goto fail;
1876         dev->dev->bNumConfigurations = 1;
1877         dev->dev->bcdUSB = __constant_cpu_to_le16 (0x0200);
1878
1879         /* triggers gadgetfs_bind(); then we can enumerate. */
1880         spin_unlock_irq (&dev->lock);
1881         value = usb_gadget_register_driver (&gadgetfs_driver);
1882         if (value != 0) {
1883                 kfree (dev->buf);
1884                 dev->buf = NULL;
1885         } else {
1886                 /* at this point "good" hardware has for the first time
1887                  * let the USB the host see us.  alternatively, if users
1888                  * unplug/replug that will clear all the error state.
1889                  *
1890                  * note:  everything running before here was guaranteed
1891                  * to choke driver model style diagnostics.  from here
1892                  * on, they can work ... except in cleanup paths that
1893                  * kick in after the ep0 descriptor is closed.
1894                  */
1895                 fd->f_op = &ep0_io_operations;
1896                 value = len;
1897         }
1898         return value;
1899
1900 fail:
1901         spin_unlock_irq (&dev->lock);
1902         pr_debug ("%s: %s fail %Zd, %p\n", shortname, __FUNCTION__, value, dev);
1903         kfree (dev->buf);
1904         dev->buf = NULL;
1905         return value;
1906 }
1907
1908 static int
1909 dev_open (struct inode *inode, struct file *fd)
1910 {
1911         struct dev_data         *dev = inode->u.generic_ip;
1912         int                     value = -EBUSY;
1913
1914         if (dev->state == STATE_DEV_DISABLED) {
1915                 dev->ev_next = 0;
1916                 dev->state = STATE_OPENED;
1917                 fd->private_data = dev;
1918                 get_dev (dev);
1919                 value = 0;
1920         }
1921         return value;
1922 }
1923
1924 static struct file_operations dev_init_operations = {
1925         .owner =        THIS_MODULE,
1926         .llseek =       no_llseek,
1927
1928         .open =         dev_open,
1929         .write =        dev_config,
1930         .fasync =       ep0_fasync,
1931         .ioctl =        dev_ioctl,
1932         .release =      dev_release,
1933 };
1934
1935 /*----------------------------------------------------------------------*/
1936
1937 /* FILESYSTEM AND SUPERBLOCK OPERATIONS
1938  *
1939  * Mounting the filesystem creates a controller file, used first for
1940  * device configuration then later for event monitoring.
1941  */
1942
1943
1944 /* FIXME PAM etc could set this security policy without mount options
1945  * if epfiles inherited ownership and permissons from ep0 ...
1946  */
1947
1948 static unsigned default_uid;
1949 static unsigned default_gid;
1950 static unsigned default_perm = S_IRUSR | S_IWUSR;
1951
1952 module_param (default_uid, uint, 0644);
1953 module_param (default_gid, uint, 0644);
1954 module_param (default_perm, uint, 0644);
1955
1956
1957 static struct inode *
1958 gadgetfs_make_inode (struct super_block *sb,
1959                 void *data, const struct file_operations *fops,
1960                 int mode)
1961 {
1962         struct inode *inode = new_inode (sb);
1963
1964         if (inode) {
1965                 inode->i_mode = mode;
1966                 inode->i_uid = default_uid;
1967                 inode->i_gid = default_gid;
1968                 inode->i_blksize = PAGE_CACHE_SIZE;
1969                 inode->i_blocks = 0;
1970                 inode->i_atime = inode->i_mtime = inode->i_ctime
1971                                 = CURRENT_TIME;
1972                 inode->u.generic_ip = data;
1973                 inode->i_fop = fops;
1974         }
1975         return inode;
1976 }
1977
1978 /* creates in fs root directory, so non-renamable and non-linkable.
1979  * so inode and dentry are paired, until device reconfig.
1980  */
1981 static struct inode *
1982 gadgetfs_create_file (struct super_block *sb, char const *name,
1983                 void *data, const struct file_operations *fops,
1984                 struct dentry **dentry_p)
1985 {
1986         struct dentry   *dentry;
1987         struct inode    *inode;
1988
1989         dentry = d_alloc_name(sb->s_root, name);
1990         if (!dentry)
1991                 return NULL;
1992
1993         inode = gadgetfs_make_inode (sb, data, fops,
1994                         S_IFREG | (default_perm & S_IRWXUGO));
1995         if (!inode) {
1996                 dput(dentry);
1997                 return NULL;
1998         }
1999         d_add (dentry, inode);
2000         *dentry_p = dentry;
2001         return inode;
2002 }
2003
2004 static struct super_operations gadget_fs_operations = {
2005         .statfs =       simple_statfs,
2006         .drop_inode =   generic_delete_inode,
2007 };
2008
2009 static int
2010 gadgetfs_fill_super (struct super_block *sb, void *opts, int silent)
2011 {
2012         struct inode    *inode;
2013         struct dentry   *d;
2014         struct dev_data *dev;
2015
2016         if (the_device)
2017                 return -ESRCH;
2018
2019         /* fake probe to determine $CHIP */
2020         (void) usb_gadget_register_driver (&probe_driver);
2021         if (!CHIP)
2022                 return -ENODEV;
2023
2024         /* superblock */
2025         sb->s_blocksize = PAGE_CACHE_SIZE;
2026         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
2027         sb->s_magic = GADGETFS_MAGIC;
2028         sb->s_op = &gadget_fs_operations;
2029         sb->s_time_gran = 1;
2030
2031         /* root inode */
2032         inode = gadgetfs_make_inode (sb,
2033                         NULL, &simple_dir_operations,
2034                         S_IFDIR | S_IRUGO | S_IXUGO);
2035         if (!inode)
2036                 return -ENOMEM;
2037         inode->i_op = &simple_dir_inode_operations;
2038         if (!(d = d_alloc_root (inode))) {
2039                 iput (inode);
2040                 return -ENOMEM;
2041         }
2042         sb->s_root = d;
2043
2044         /* the ep0 file is named after the controller we expect;
2045          * user mode code can use it for sanity checks, like we do.
2046          */
2047         dev = dev_new ();
2048         if (!dev)
2049                 return -ENOMEM;
2050
2051         dev->sb = sb;
2052         if (!(inode = gadgetfs_create_file (sb, CHIP,
2053                                 dev, &dev_init_operations,
2054                                 &dev->dentry))) {
2055                 put_dev(dev);
2056                 return -ENOMEM;
2057         }
2058
2059         /* other endpoint files are available after hardware setup,
2060          * from binding to a controller.
2061          */
2062         the_device = dev;
2063         return 0;
2064 }
2065
2066 /* "mount -t gadgetfs path /dev/gadget" ends up here */
2067 static struct super_block *
2068 gadgetfs_get_sb (struct file_system_type *t, int flags,
2069                 const char *path, void *opts)
2070 {
2071         return get_sb_single (t, flags, opts, gadgetfs_fill_super);
2072 }
2073
2074 static void
2075 gadgetfs_kill_sb (struct super_block *sb)
2076 {
2077         kill_litter_super (sb);
2078         if (the_device) {
2079                 put_dev (the_device);
2080                 the_device = NULL;
2081         }
2082 }
2083
2084 /*----------------------------------------------------------------------*/
2085
2086 static struct file_system_type gadgetfs_type = {
2087         .owner          = THIS_MODULE,
2088         .name           = shortname,
2089         .get_sb         = gadgetfs_get_sb,
2090         .kill_sb        = gadgetfs_kill_sb,
2091 };
2092
2093 /*----------------------------------------------------------------------*/
2094
2095 static int __init init (void)
2096 {
2097         int status;
2098
2099         status = register_filesystem (&gadgetfs_type);
2100         if (status == 0)
2101                 pr_info ("%s: %s, version " DRIVER_VERSION "\n",
2102                         shortname, driver_desc);
2103         return status;
2104 }
2105 module_init (init);
2106
2107 static void __exit cleanup (void)
2108 {
2109         pr_debug ("unregister %s\n", shortname);
2110         unregister_filesystem (&gadgetfs_type);
2111 }
2112 module_exit (cleanup);
2113